Apparatus for the production of comminuted particles



June 10, 1947. s HILLER 2,422,099

APPARATUS FOR THE PRODUCTION OF GOMMINUTED PARTICLES Original Filed Jan.3, 1941 a s 2- 54/31 26 5 t I 8W ATTORNEY vided Patented June 10, 1947APPARATUS FOR THE PRODUCTION OF COMMINUTED PARTICLES Siegfried H ll w rN Y- O si a a l ation J a ,3, 19 1, a No,

1944, Serial No. 541,180

4 Claim- This invention relates to apparatus for the production .ofcomminuted particles, in particular particles of metallic oxides andrelated prod.- uct-s, and includes correlated improvements designed toenhance the utility of such apparatus.

In my U. S. Patent No. 2,213,365 issued September 3, 1940 entitledpparatus for the production of powders of low meltingepoint metals .orof compounds thereof, I have described an apparatus including anatomizing chamber for producing finely co-mminuting metallic particles.

Comminuted metallic particles which are thus formed pass directly intoan ,oxidizing chamber where the lighter particles become oxidized andare drawn off, while heavier particles fall back paratus.

It is also desired to provide apparatus for combining the smalleruniform metallic particles with various gaseous reagents to formcompounds or derivatives thereof and collect the'same in a finelydivided comminuted state.

It is a general object of the present invention to provide an apparatusfor the production of finely divided comminuted metallic particles,oxides, or other compounds in a continuous operation.

It is a specific object of the present invention to provide in anapparatus for the formation of comminuted metallic particles, means forseparating the smaller particles from the larger particles and reactingsuch to the smaller particles with gaseous reagents.

It is a further object of the present invention to provide in anapparatus for producing comminuted metallic particles, meansfor-rejecting larger particles which may be formed along with thesmaller comminuted metallic particles, select ing the smaller particles,and means for collecting the smaller particles thus selected.

Other objects will inpart be obvious and will in part appearhereinafter.

Thus, in an apparatus which is suitable for carrying out the presentinvention there is pro means for melting a low melting point separatingth 1;

Divided and this'applicatio'n June '20,

meta means for comm utins sa d metal to form cqmminute m tal ..,tiQ1 thee f. means for le paticl s rom the smaller and lighte part les. t us :fom d, means for returning said heavier particles to the molten metal, andmeans for co lectin the lighter partic es in a finely divided state.

The invention accordingly compris s he features of construction,combinations of elements. and arrangement of parts, which will beexemplified in the construction hereinafter set forth and the scope ofthe invention will be indicated in the claims. 7

According tothe present invention, there is also provided in anapparatus for the production .of comminuted metallic particles orcompounds thereof, in combination, a vessel in which metal may bemelted, a comminuting unit comprising a rotatable fiinger, wheel, acasing for said flinger wheel, an inlet in the bottom of said casing foradmitting a portion of molten metal from the melting vessel, an outletfor said casing comprising a Side duct and a combustion chamber con.-nected to said side duct, means for producing .comminuted metallicparticles in said comminuts ing unit and conveying said particles intothe combustion chamber, and means for collecting the lighter particlesthus formed. while returning the heavier particles to said reservoirwithout permitting the particles to re-enter the comminuting chamber..In a preferred embodiment there is also provided within said combustionchamber a reaction zone for forming pure me tallic particles, themetallic oxides, or various other chemicalcompounds thereof, as saidfiner comminuted particles are being passed through said chamber.

Various low melting-point metals which may be employed to formcomminuted metallic par-,- ticles comprise such metals as copper, lead,tin, brass, antimony, zinc, cadmium, and the alloys which may be formedof the various meals, and the like.

."Reagentswhichmay be used to react with such metals inthe .comminutedstate to form various compounds thereof comprise various reactive gasesor vapors, such as which form metallic oxides, sub-oxides, and the like.Other reactive gases mine, iodine, hydrogen sulfide, sulphur, carbondioxide and the'like maybe used to form halides, sulfides, carbonatesand other compounds with thelcomminuted metals. Mixturespf these vari.ous gases may be used to form.other derivatives of ,the. metallicparticles, and which also may air, steam or oxygen such as chlorine,bro.-

depend upon operating conditions, such as temperature, pressure and thelike.

Alternatively, suitable inert gases may be employed to prevent theformation of compounds or derivatives of the various metals, forexample, T

such gases as helium, carbon monoxide, nitrogen, and other inert gases.Such gases may be used to create an inert atmosphere to provide for theformation of comminuted metallic particles in a substantially unreactedstate. Under other con- I ditions hydrogen may be employed either as areactant to reduce metallic compounds which may be formed, or toinitially prevent the formation of such compounds.

For the combustion chamber there may be employed any of a, wide varietyof furnaces, burners or ovens which are used to burn the variousatomized or vaporized combustibles such as gases, fuel oil, powderedcoal, coke dust, and the like. In a, preferred embodiment there isprovided a modified combustion chamber adapted to burn a gas, or toprovide other means for initiating a reaction between various gaseousreagents and the] comminuted metallic particles causing them to igniteor otherwise combine to form compounds jects of the invention referenceshould be had to the following detailed description taken in connectionwith the accompanying drawings, in which:

Fig. 1 is a view of a section in elevation of one form of apparatussuitable for carrying out the process of the invention; and

' Fig.2 is a partial end view ofa section of Fig. 1 taken at 2--2.

Referring to Fig. 1', there is provided a furnace II) supporting VesselI I in which metal is melted to form molten metal I2. The furnace I0 maybe heated by any suitable means, such as. coal, coke, oil or gas. Aportion of the hot waste gases formedin furnace It may be drawnoff bymeans of conduit I3 and utilizedv to preheat atomizing chamber I5.

The atomizing chamber I5 comprises a housing or casing I4 whichispreferably of an insulated type having a thick wall. In the bottom ofsaidatomizing chamber there is provided one 'or' more openings I! towhich there are attached tubes I8, which permit a portion of the moltenmetal I2 to enter the comminuting chamber by gravity flow. Thereisprovided in said atomizing chamber a flinger wheel I6 adapted to rotatewithin' the atomizing chamber and which may be rotated by shaft 20. Theshaft may be driven by any suitable driving means, such as by beingcoupled directly to an electric motor or to a pulley and belt (notshown). One side of the atomizing chamber I5 is provided with an outletduct I9 which is in turn connected with combustion chamber 2|, the lowerportion122 of said chamber dippinginto the surface of molten metal I2;Within the combustion chamber 2| there is provided a plurality ofjets ortuyeres 23 substantially near the central portion of said chamber,'Whichjets are adapted to burn a light fuel, gasor oil if initial heat isfoundfdesirable or necessary. In the preferred embodiment a combustiblefuel or gas, such as water gas, hydrogen sulfide, or a halogen may beintroduced by means of supply pipes 24,and the jets 23 supplied with asuitable gas, such as air or oxygen,

by means of pipes 26. Alternatively; a spark gap 4 may be used in placeof the flame jets, or reacting gases such as chlorine, hydrogen sulfide,and the like may be admitted by means of the jets to form variousmetallic derivatives of the comminuted metallic particles; or such jetsmay be used to introduce an inert gas. The air or other gases may bepreheatedby. passing pipes 26 through preheaters 21 comprisingfire-brick surrounding the combustion chamber and arranged about thereaction zone 3|.

Combustion chamber 2| is shown as having a construction 31 near the topportion, so that comminuted particles which are carried upwardly fromreaction zone 3| may be drawn off and/or burned in secondaryv burningzone 33. An excess volume of air may be admitted to the secondaryburning Zone 33 by a draft created between dome 3d and collar 35, whichdraft intake is shown by direction arrows A. If desired, incompletecombustion reactions may be conducted with the metallic particles toform sub-oxides of .the metals, or a mixture of pure metallic particlesand oxides thereof, or other various derivatives,

by lowering or raising the dome 34 to admit larger or smaller volumes ofair, as required. Al-' ternatively, the dome may be lowered all the way,whereupon the dome makes a tight fit with collar 35, thus excluding air'entirely. Thus air may be excluded entirely from zone 33 when it isdesired to form the metal in comminuted me.- tallic form, or when itisdesired to form the'sulfides, chlorides, carbonates or metallicderivatives of the metals other than the oxides. The particles may bedrawn ofi by suitable known means, such as by means of a draft ornegative pressure created within the dome and for com- 7 v bustionchamber by a suction fan, vacuum or blower attached to neck 32 (notshown).

Referring to Fig.2, a portion of the combustion chamber is broken awayto show the flinger wheel 16 within casing I4 and to show itsrelationship with the combustion chamber 2|. Particles of the comminutedmetal'a re carried upwardly through the reaction zone 3|, which zone maybe supplied with suitable gases by means of the jets 23, as described.The heavier particles formed during the comminuting process and whichare carried into the vertical chamber" 2| are returned to the vessel I Iby gravitational differentiation or by adjustment of the amount ofsuction or negativepressure, and are thus re:

united with the'molten metal I2, while the lighter particles are carriedupwardly in the combustion chamber, thus preventing direct return of theheavier particles of the atomizing chamber. V

In utilizing the apparatus of'the invention, a suitable quantity ofmetal is melted in the melting vessel or reservoir I I and after,sufficient heating a. quantity of the molten metal is introduced bygravity flow ,intoatomizing chamber I5 where it contacts the flingerwheel I6. Theflinger wheel is rotated within the atomizing chamber at avelocity suitable to create a mist comprising particles'of said molten'metal. The majority of the particles thus formed .find their way'or aredriven out of the atomizing chamber through.

side duct I9 and into combustion chamber 2|. It willlbe noted thatsideduct. I9 is close-coupled with the combustion chamber 2| in order tofacilitatethe passage 'of the'comminuted' par ticles from the'atomiz'ingchamber into the lower 7 part or the combustion chamber; Aportion' ofthe heavier particles formed during .the atomiz- ;ing,process strikethe, inner wall 29. of said cham.- her and drop-directly into reservoirII containing the-moltenmetal. .Othtirheavier particles which .maybecarried-along with the finely comminuted particles gradually drop backinto the reservoir .H as the :finer particles continue their :upwardtravel through :the combustion zone 31, where thcymay be ignited to formthe various comminuted metallic oxides or other compounds.Alternatively, the ianitioniets :2 3 may :be .used to introducean inertgas-or they maybe closedofi or omitted entirely. In many cases, afterthe me- :tallic particles have been ignited :for a short period not timeand aftera suff cient temperature has *been so maintained, theinitialsupply of fuel orgas introduced by jets 23 may be cut off and theburning of such metallic particles sustained ;,by merelyintroducing intothe combustion chamber an adequate supply .of-preheated;air bymeans .ofsupply pipes 126. Furthermore, other metallic particles, such :as thoseformed of Zinc or tin, may becomeignited and burn without-thenecessityof the :pre-ignition touinitiate the combustion.

melting vessel H in quantity sufficient to flow into the atomizingchamber l5 by means of openings I7 and contact the flinger wheel [6. The.fiinger Wheel is rotated at a velocity suiiicient to create a mistcomprising a plurality of comminuted particles of molten metal withinthe atomizing chamber 55. Preferably, the atomizing chamber is preheatedby means of conduit I 3 to prevent the particles from freezing againstthe Walls of the atomizing chamber. The majority of the particles thusformed find their Way into the vertical combustion chamber 2| by meansof the outlet duct 19. The majority of the heavier comminuted particlesstrike the wall '29 of the-combustionchamber and drop back into vessel Hcontaining the molten lead. Ina preferred embodiment (not shown) thereis provided a striking plate formed of heavy metal removably attached tothe inner wall .29 which may be replaced from time to time as required.The remaining comminuted metallic particles are carried upwardly throughthe combustion chamber, and leave the combustion chamber by means of theconstricted portion 31 and are carried away by a reduced pressurecreated Within the dome 34. As the particles travel upwardly through thecombustion chamber 2| the remaining heavier lead particles are separatedfrom the finely comminuted particles by gravitational differentiationand drop directly into the vessel containing the molten lead by means ofthe open end portion 22. The finely comminuted lead particles are drawnoff at 32 and collected in known manner.

In the preferred embodiment the finely comminuted lead particles areignited in ignition zone 3|. Suitable ignition means for the burning ofsuch finely divided particles is provided by jets 23. Such ignition iscreated by the introduction of a mixture of air and gas, such gascomprising a natural gas or methane. Burning is initiated by means ofair pipes 26 and gas pipes 24. As the finely divided lead particles areignited they are carried upwardly into :a second ignition :zone :33where further burning occurs. Sufiicient air to sustain the secondaryburning of the particles is introduced between the dome 34 and collar35, shown by direction arrows A. The lead oxide thus formed .is drawnoff at; .32 in a substantially finely divided .comminuted state.

Alternatively, pure particles of lead of afinely dividedand uniform sizemaybe :formed hydroptpingthe dome 34 to form a tight lit with collar :35and closing jets 2:3, or introducing an inert gassuch as nitrogen inplace of the ai and/or methane .gas. The finely dividedparticlesofunreacted lead of uniformsize are, then drawn on? at .32 asdescribed above. In place of vforming xfinely divided particles ofunreacted lead or'lead oxides, lead sub-oxides may be formed byintroducing an insuificient supply of air or oxygen.

ad sulfides may be formed by admitting .hydrogen sulfidetothezcom'bustion zone 3l-in place of air or oxygen. Qhlorides, carbonates,andiother lead compounds maybe formedin like manner by substitutingother suitable gaseous reagents intothe combustion chamber.

Amon the advantages realized by the EPI'BSEDIJ invention, it will bobserved that by the gravitational return-of the larger particles to thereservoir containing the molten metal the atomizing chamber isrelievedof suchrejectedmaterial,

thus overcoming the danger of fouling and/or clogging the *flingerwheel.

Other advantages such as lowered operating costs, reduction in fuelconsumption and thelike are realized due to the light construction ofthe apparatus and arrangementof the integral parts.

The comminuted metallic particles, formed -according .to the presentinvention are ina form readyfor euse inmetallic paints, storage.batteries,

and a wide variety of .other products and articles ofmanufacture.

Since certain changes may be made .in the above construction anddifferent embodiments of the invention .could ,be .made withoutdeparting fromthe scope thereof, itis intended that all matter containedin the above description or shown in the accompanying drawing shall:beinterpreted as illustrative and not in .a limiting sense.

It isa'lso to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed, and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

This application is a division of my copending application Ser. No.372,980 filed January 3, 1941, now Patent 2,358,068, issued Sept. 12,1944.

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

1. In an apparatus for producing comminuted metallic particles, thecombination of a vessel for maintaining a mass of molten metal, adrumshaped chamber having an opening therein for admitting said moltenmetal and an outlet to permit discharge of molten particles therefrom, afiinger wheel rotatably mounted within said chamber, said fiinger wheelprovided with fins for comminuting and projecting said molten metal in acomminuted state, a vertically extending combustion chamber mountedadjacent to said drumshaped chamber and connected through an aper- 7tioned to extend downwardly into the vessel with an opening in thebottom thereof, so that heavier particles falling from a comminuted massof particles projected therein are returned by gravity to said vessel ata point removed from said drumshaped chamber after entering thecombustion chamber through said aperture.

2. In an apparatus for producing comminuted metallic particles, thecombination of a vessel for maintaining a mass of molten metal, adrumshaped chamber having an opening therein for admitting said moltenmetal and an outlet to permit discharge of molten particles therefrom, afiinger wheel rotatably mounted within said chamber, said flinger wheelprovided with'fins for comminuting and projecting said molten metal in acomminuted state, a vertically extending combustion chamber mountedadjacent to said drum shapedchamber having jets therein for admttinggases, said combustion chamber con- 'nected with said drum-shapedchamber through an aperture in the side thereof to receive thecomminuted particles of molten metal as they leave said drum-shapedchamber, said combustion chamber positioned substantially perpendicularto the surface of said vessel and extended downwardly into the vesselwith an opening in the bottom thereof, so that heavier particles fallingfrom a comminuted mass of particles projected therein are returned bygravityto said vessel at a point removed from said drum-shaped chamberafter entering the combustion chamber through said aperture. r

3. In an apparatus for producing comminuted metallic particles, thecombination of a vessel 7 for maintaining a mass of molten metal, adrumshaped chamber having an opening therein for admitting said moltenmetal and an outlet to permit discharge of molten particles therefrom, aflinger 'wheel rotatably mounted within said chamber, said fiinger wheelprovided with fins for comminuting and projecting said molten'metal in acomminuted state, a vertically extending combustion chamber mountedadjacent to said drumshaped chamber and connected through 'an aperturein the side thereof to receive the comminuted particles of molten metalas they leave said drumshaped chamber, the combustion chamber positionedsubstantially perpendicular to the surface of said vessel and extendeddownwardly into the vessel with an opening-in the bottom thereof, sothat heavier articles falling from the comminuted mass of particlesprojected therein are directly returned by gravity to said vessel,tuyres mounted within said 0 mbustion chamber for admitting gases tosaid chamber, and a dome equipped with'a suction device attached to thetop of said combustion chamber whereby'lighter particlesprojected'within saidchamber may be removed through said dome whileheavier metallic particles are gravitationally returned to said vesselat a point removed from said drum-shaped 7 chamber after entering thecombustion chamber through said aperture.

7 4. In an apparatus for producing comminuted metallic particles, thecombination of a vessel for maintaining a mass of molten metal, meansfor heating said vessel, a drum-shaped chamber having an opening thereinfor admitting said molten metal and an outlet to permit discharge ofmolten particles therefrom, a fiinger wheel rotatably mounted withinsaid drum-shaped chamber, said flinger wheel provided with fins forcomminuting and projecting said molten metal in a comminuted state, avertically extending combustion chamber mounted adjacent to saiddrum-shaped chamber and connected through an aperture in the sidethereof to receive the comminuted particles of molten'metal as theyleave said drumshaped chamber, a dome positioned .above said combustionchamber and adapted to engage therewith, and a suction device coupledwith said,

dome for removal of the smaller particles from said combustion chamberwhile heavier metallic particles are gravitationally returned to thesaid vessel containing the molten metal at a point removed from saiddrum-shaped chamber after entering the combustion chamber through saidaperture.

. SIEGFRIED HILLER- REFERENCES crrsn The following references are ofrecord in the file of this patent: i a

UNITED STATES PATENTS g 7 7 Date Certificate of Correction Patent No.2,422,099: June 10, 1947.

SIEGFRIED HILLER It is hereby certified that errors appear in theprinted specification of the above numbered patent requiring correctionas follows: Column 2, line 42, for meals read metals; column 4:, line12, for construction read constriction; and that the said Letters Patentshould be read with these corrections therein that the same may conformto the record of the case in the Patent Office.

Signed and sealed this 11th day of November, A. D. 1947.

THOMAS F. MURPHY,

Assistant Commissioner of Patents.

